As demonstrated in Fig. REF , the higher dimensional topological phases supply fundamentally ways of topological wave steering, whose possible applications remain to be discovered. Nevertheless, we already envision radically directions in mode steering, which can be useful for information processing. Indeed, the phason trajectory reported in Fig. REF  is special in two respects: it has non-trivial topology and it occurs at constant frequency. As such, a coherent drive of the phason along that trajectory will not only steer the mode around the sample, as seen in Fig. REF , but will also generate temporal de-phasings that can be computed as Berry phases. In fact, the bulk modes can be also manipulated in a similar way, by driving the phason along topologically distinct loops inside the phason space. As already envisioned in [1]} such controlled temporal de-phasings could be used for certain forms of information processing.
